Talk:Kilogram

Definition of Kilogram

All terms of science, including units of measure, use operational definitions, that is, definitions based on actually performable experiments and observable results. The kilogram is intended to represent the mass of one litre of water (where litre is defined in terms of metre, and metre is defined in terms of the measurable speed of light), but that's a theoretical thing --it's not possible with today's technology (nor was it in the past) to conduct any specific experiment with water to produce this value. The kilogram has always been officially defined in terms of the artifact in Paris (the metre once was as well, but now we have new experiments). There is a movement among some scientists now to redefine it in terms of a new experiment in which measurable electrical potentials move a specific mass, but this is still in the works. --LDC

The kilogram as = 1 L of water was true between 1901 and 1964 (definition of the Litre; see CGPM).

Urhixidur 20:29, 2004 Nov 23 (UTC)

I was under the impression that the kilogram had recently been redefined in relation to x moles of a certain isotope, rather than the kilogram at Sèvres. Is that not true? - montréalais

There are a number of competing plans to redefine the kilogram in terms of something repeatable. No plan has yet been decided on. -- The Anome 22:10 22 Jun 2003 (UTC)

According to the Bureau International des Poids et Mesures, the kilogram is still defined by the international prototype in Paris. Do you think it's fair use to put a picture of it from the BIPM site in the article? Basil Fawlty 15:12 22 Jun 2003 (UTC)

Seems like it would be fair if the source and a disclaimer tag were included. As the fair use page states, "Unique historical images which we cannot reproduce by other means" can be classified as fair use. The big pic is nice. -- Mjwilco 19:12, 11 Sep 2004 (UTC)

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What does this mean: "grain in now obsolete Portuguese spelling"? Is that supposed to imply that the word "gram" comes from obsolete Portuguese? Webster's 1913 says: "F. gramme, from Gr. ? that which is written, a letter, a small weight, fr. ? to write.". Or is it some weird reference to the imperial unit grain, meaning 1/7000 of a pound? -- ESP 05:37 20 Jul 2003 (UTC)

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Am I right in assuming that, by E=mc^2, if you heat an object, you will (ever-so-slightly) increase its mass, by adding thermal energy? (according to [[1]] to heat 1 gram of water by 1 degree C, requires ~0.465 femtograms of energy. Therefore any atom-based definition of the kilogram will require a temperature reference. CS Miller 11:39, Nov 23, 2004 (UTC)

You are quite right. In Einsteinian terms, we would refer to the zero K mass as the object's rest mass. Note that the SI definition of the second also takes care to specify that the ground state hyperfine transition used occurs at zero K.

Urhixidur 20:29, 2004 Nov 23 (UTC)

Kilogram as Base unit?

Has the kilogram always been considered a base unit? If so, why does it have a prefix? Why doesn't the metric system use a basic word for that unit, and instead call the gram milli-whatever? If it wasn't considered a base unit initially, when did it come to be considered the base unit? It has always seemed strange to me that a so-called "base" unit has a prefix Nik42 09:00, 26 Jan 2005 (UTC)

It really is quite stupid, but its too late to change that now :P. My theory is that the gram initially was the base unit, but people realised that it was smarter to use kg (less room for error when copying the base-sphere, and also derived definitions like the newton make more sense. That and it would be strange to measure the human body in grams "I weigh 75345 g, what do you wheigh?) So they just changed the base and kept the name to avoid confusion. This is my theory anyway Gkhan 04:33, Feb 27, 2005 (UTC)

Well, the weight thing's not really an issue. That's what prefixes are for anyways :-) I mean, no one would say that two cities were 52,000 meters apart, they'd say they were 52 kilometers apart. Still, kg definitely does make more sense as a basic unit for pretty much any purpose, which is why I find it odd that gram gets the basic name. - Nik42 07:50, 1 Mar 2005 (UTC)

Originally, the kilogram was supposed to be called the grave. The "new" system of units was commisioned by Louis XVI. A milligrave was to be 1/1000 of a grave, a kilograve 1000 graves. However, didn't come in effect until after the French Revolution. (Especially measuring the earth for defining the metre as one ten-millionth of the length of the earth's meridian along a quadrant, took a lot of time and was complicated by this Revolution) After the Revolution, the name "grave" was politically incorrect, because it is an alternative name for the title "count", and titles aren't compatible with the notion of égalité.

Also, scientists and industrialists feared that a grave would be too big or small for every-day use, so they choose gramme and tonne instead. But then that turned out to be to small or big, especially to make a defining prototype of, so they defined the original proposal (grave) under a different name (kilogram).

Or something like it.

See http://www.bipm.org/en/si/history-si/name_kg.html

All of that was already included in a summary of the above in the grave article, though.

–Adhemar

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AFAIK there is no atomic definition for kilogram. In 1967 the kilogram[2] was defined as the mass of 5.0188 X 10 (power 25) atoms of the carbon isotope of atomic mass number 12. The experimental uncertainty in the count was about 1 part in 20,000. -- Orionix 03:11, 4 Feb 2005 (UTC)

Clarify changes over the last 100 years

From the article: Although it is accurate to state that all other objects in the universe have gained 50 micrograms per kilogram, this perspective is counterintuitive and defeats the purpose of a standard unit of mass.

This makes no sense to me. If you counted the number of micrograms in a kilogram 100 years ago, you'd get a billion (if my metric conversions are correct). And the article is implying that if you count the number of micrograms in a kilogram today, you'd get 1,000,000,050? Wrong.

Maybe a more clear way to say it would be "It is accurate to state that any object in the universe (other than the reference metal in France) that had a mass of 1 kilogram 100 years ago, and has not changed since then, now is considered to have a mass which is 50 micrograms larger than a kilogram. This perspective is counterintuitive and defeats the purpose of a standard unit of mass, since the standard should not change arbitrarily over time."

--24.29.11.65 11:27, 27 Feb 2005 (UTC)

How is it known that the standard has lost weight? How can one compare a standard to itself over time? It seems like a paradox to me. Prometheus235 19:03, 16 Jun 2005 (UTC)

Presumably because you can compare the weight of other objects over time. If you consistently find that items measured 100 years ago appeared to possess slightly greater mass than they do today, the simplest explanation is not that all of those items gained mass, but that the standard lost mass. - Nik42 18:25, 17 Jun 2005 (UTC)

Also the standard has "official copies" that are stored and treated in the same manner as the standard itself. What's actually been found is that the standard is lighter in comparison to the average of these copies than it previously was. Pakaran 19:12, 17 Jun 2005 (UTC)

I think the whole paragraph save the first two sentences should be removed. I'm not going to edit it cause no-one else seems to have an issue but I mean, 1. the average person out there is (probably) going to be confused by it and 2. it's not really true; yes, in a way, everything has gained 50 micrograms relative to the SI mass, but our very awareness of this fact means that things haven't gained 50 micrograms from our perspective. It's a lot like saying "My bathroom scale is calibrated slightly high, therefore I have gained weight and need to diet", which is just silly. 202.37.62.123 04:11, 5 January 2007 (UTC)

I agree with you, actually. I'd integrate those first two sentences into the previous paragraph, and the result would be shorter and clearer. While the current version IS amusing and I love the word "paradoxical", I think we should be striving to be concise and understandable, not eccentric and amusing. In fact, I will (assuming we don't get a flood of comments here) integrate those first two sentences and delete the rest if you don't get to it in a few days. Enuja 05:18, 5 January 2007 (UTC)

Move the Article to "Kilogramme"

Wikipedia:Standardize Spellings specifies that articles may be written in either American or Commonwealth English depending on the subject matter. Seeing as how a kilogram is not a standard measure in America, it makes more sense in my opinion for this article to be moved to "kilogramme."

Where is the spelling "kilogramme" used? And it is used as a unit of mass in both North America and South America. 64.7.152.217 20:40, 13 September 2005 (UTC)

Well, it is used in scientific measurements, but not generally in commerce, in the US, where we tend to measure masses in terms of pounds. I am fairly certain than in all other parts of the Americas, the kilogram is the standard, including Canada, an English-speaking country. However, I would argue that it is not commonly spelled out. In fact, I would reccomend that the article be named kg (SI unit), and both spellings redirect to that, and all other SI units be named the same way. Unfortunately we have the majescule (capital) article title problem to deal with. --Mm35173 20:30, 28 September 2005 (UTC)

The United States was an original signer of the Meter Convention treaty of 1875; the U.K. didn't get on the bandwagon until decades later.

In case User: 64.7.152.217 is the "Commonwealth" version of Rip Van Winkle and hasn't noticed it yet, the kilogramme spelling has nearly completely disappeared from the rest of the English-speaking world as well. Gene Nygaard 15:46, 20 October 2005 (UTC)

You have you dates wrong I’m afraid, the US joined in 1878 and the UK in 1884 so that’s hardly decades is it? But yes you’re right, the US did sign first, however I’d argue since in real terms the US did not, and still does not really use the metric system whereas the rest of the English speaking world does, and bar perhaps Canada, spells it kilogramme then the article ought to be changed to reflect this. This would bring into line the English spelling with the original French spelling and the spelling of many other languages. Furthermore most of the other metric system measurements are listed in Commonwealth English so it is a bit of a mess to have most of the Metric system spelt in one convention but the remaining bit in another convention.

I wouldn't call the spelling "Kilogramme" a feature of Commonwealth spelling, I'd say it's an anomalous spelling only encountered in the UK. In Australia (which derives most spellings from Commonwealth English) the form "kilogram" is used exclusively. I'd be willing to bet it's the same in most Commonwealth countries. Leave the article where it is.--Scott Nash 05:23, 8 July 2006 (UTC)

The spelling kilogramme and gramme is pretty much restricted to the UK in the English speaking world. Even in the UK it's pretty rare nowadays. Therefore it certainly doesn't make sense to change an article from a majority spelling to a minority one. Leenewton 23:05, 8 February 2007 (UTC)

Removal of SI multiples section

User:Lee S. Svoboda recently deleted the SI multiples section, replacing it with a redirect to SI prefix.

That is unacceptable. What used to be separate articles at milligram and microgram and gigagram and the like now redirect here, to kilogram (megagram redirects to tonne, however). Part of the reason for including the prefixes here (and to similar unprefixed units for other quantities--the prefix is only included here because it is included in the SI base unit) was that people getting redirected here from a link to a prefixed unit were not finding anything about what the prefix means (and that's likely to be the main reason they click on a link to a prefixed unit). Part of the deal on eliminating the separate articles for the prefixed unit is that this information would be included in articles such as this one, not requiring people to chase all around the Wikipedia to find what they were looking for. Gene Nygaard 15:59, 20 October 2005 (UTC)

Approximate equivalent in pounds?

The absence of Imperial/US equivalents seems to be a major omission to me. Grant65 (Talk) 13:22, 13 November 2005 (UTC)

• The category link to "units of mass" is sufficient. Długosz

mcg for micrograms

Recently, an edit claiming that mcg is occasionally used for micrograms was reverted. The prefix mcg is used when the µ symbol isn't available, particularly in the medical field. Andros 1337 00:36, 23 November 2005 (UTC)

ug for migrograms

I see there is a citation request for the use of u for micro. In http://www.cofc.edu/~frysingj/lowtech.htm, the author cites the following reference:

American National Standard Letter Symbols for Units of Measurement (SI Units, Customary Inch-Pound Units, and Certain Other Units, ANSI/IEEE Std 260.1-1993 (Institute of Electrical and Electronics Engineers, New York, NY, 1994) section 6.1

I don't have access to that publication, but maybe someone who does can check it out? --Slashme 07:19, 21 July 2006 (UTC)

According to that link, u is the accepted workaround for use where one cannot use the greek letter mu (μ). The section on mu is:

For the lower case Greek letter mu, used to symbolize the prefix 'micro', use the lower case letter "u".
example:
    "The hair diameter is 68 µm."
    "The hair diameter is 68 um."
    (or "The hair diameter is sixty-eight micrometers.")
(note:  In typewritten texts, a "tail" should be added to the "u" by hand.) 

what coefficient?

I don't understand what is meant by: "The coefficient is close to the reciprocal of Avogadro's number: 1 unified atomic mass unit = 1.660 54 yg". What coefficient is being refered to here? The number in the sentence is exactly Avogadro's number. —Długosz

difrents

a kilogram is heveyer than a acsholy is little litter than a gram

you are a nonsense!

Cultural imperialism

Those 300 million of us who do not use the metric system should be informed how many pounds are equivalent to a kilogram. Lord knows the "pound" article is clogged up with kilogram crap. The article is hopelessly metric-centric, and refuses to acknowledge the existence of other units and measurements which are used by other cultures.

Go ahead, be bold, and add in the information you think is missing. Indefatigable 22:04, 19 January 2006 (UTC)

Okay, cool. I'll change it here - I would have done it earlier, but I felt like registering a complaint to draw attention to the wider unit biases on wikipedia. For instance, the total area of the U.S. state of Wyoming is given in square kilometers, with no square-mile figures provided - this for a state in a nation where the metric system is not widely used or understood. I'm unclear as to whether this bias is official policy or just a lack of information - it's so universal that it often seems to be the former. I'm trying to address the problem in general, and I might as well start here.

There is a bias because there should be. The vast majority of the world, uses metric predominantly. Even within the US, many especially scientists and engineers use professionally (and I would say prefer personally) metric. Also, while a fair number of people who use the pound and other non metric units find it necessary to have a good or excellent knowledge of conversions to metric units, many of those who use metric have only limited or no knowledge of conversions and have no real desire to know them. I'm not saying that we should ignore other unit systems or that there aren't improvements to be made but you appear to fail to appreciate how widespread metric usage is. Nil Einne 13:35, 21 June 2006 (UTC)

No doubt he has a chip on his shoulder about metric because it's French :o)

Problems of artifact definition

This article doesn't really elaborate on the problems of a physical artifact definition of the kilogram properly. It mentions the problem of a changing weight but other then that little else. However there are quite a number of problems. For starters, an artifactal definition could not be transmitted as information only. For example, we could easily send all other definitions out and in the unlikely event another intelligent race receives our signal and if they could work out our language etc they could easily understand our units and if they have a sufficient level of technology, they could therefore easily reproduce out units. However with the kilogram, all they would get/know would be that it's the same as some object stored in France which isn't particularly useful for them. This also applies for example if we were to all be wiped out or to regress to a low technological level area anyone who comes after us would have a similar problem. On a more basic level, with all other units, any scientist (or whatever) today with the required technology and understanding can indepedently measure/work out the unit. However with the kilogram, all they can do is visit their local agency and use that. Similarly although rather unlikely if some deranged person were able to get access, they could blow up or otherwise damage the kilogram and we would no longer have an official kilogram (we would have to take one of the replicas to be the new official kilogram). Or it could be lost (again very unlikely). And of course, if you want to get very sneaky, someone could replace the kilogram with an alternative thereby changing the definition of the kilogram (to some extent this is similar to the problem of a natural change to the kilogram) Nil Einne 13:56, 21 June 2006 (UTC)

In principle, aliens could work out the approximate mass by simply giving the density of certain objects. For example, 1 liter of water is very close to 1 kilogram. They wouldn't be able to derive an exact value from that, since there are variations in density based on pressure, temperature, etc., but it would be a very close approximation Nik42 02:31, 24 July 2006 (UTC)

It needs better examples in the Examples section. Check out the gram article to see what I mean.

Fundamental-constant approaches

i deleted incompletely defined "levitated superconductor approach". it does not say what physical constants are fixed to whatever value by the kg definition. it may be a perfectly good experiment to set up to define the kg, but it needs to say the definition: "the kilogram is such and such so that the physical constant so and so is set equal to some value." r b-j 21:55, 1 July 2006 (UTC)

It should be noticed that it is not possible to give an exact value to the von Klitzing constant. It equals half the speed of light times the magnetic permeability of free space divided by the fine structure constant. The speed of light and the permeability of free space are already defined as 299792458 m/s and 4π/10^7 N/A^2 respectively, so we'd need to know the exact value of the fine structure constant to do that. --Army1987 10:51, 1 August 2006 (UTC)

for some reason, when i was trying to clean up a similar sections of the definition of the Ampere, i ended up in a discussion/disagreement with User:Urhixidur at Talk:Ampere#erroneous_definition_for_Ampere. he said that:

1) CIPM, 1988, Recommendation 2 (PV, 56, 45 and Metrologia, 1989, 26, 70) recommends « that 25 812.807 W exactly be adopted as a conventional value, denoted by R_K-90, for the von Klitzing constant, R_K ».

and although i knew that it differered from CODATA and that the resulting alternative definition for the ampere (and Coulomb) could only happen as a consequence of a redefinition of the kg, i fixed it there and here in proposed redefinitions. i was trying to effect a compromise (since this was proposed definitions not the currently accepted definition) and still be accurate.

you might want to get User:Urhixidur's attention regarding this or, if you see something that is just wrong, fix it (and see if it survives). r b-j 14:58, 1 August 2006 (UTC)

i changed it. if User:Urhixidur objects, i think he has to persuasively answer User:Army1987 point (which appears perfectly valid to me). r b-j 20:32, 2 August 2006 (UTC)

multiples

Please don't remove multiples, for consistency they are in all seven base SI units.

Weight

I just added a link to the "weight" page in the "Link to Weight" section, because the section, while very explanatory, seemed over the head of a novice reader. Also, I couldn't find any other links to the weight page. If there is a better place to put the link, or if I simply missed a previous link, please change it. I know the word "weight" appears earlier in the article, but it is always a part of a title (weights and measures) or is a heading. Enuja 01:08, 5 January 2007 (UTC)

Repeatibility of Offical Standard

I combined the two paragraphs (in the history section) about the repeatibility of the standard, and took out the tangent about the change in mass of every single item, when measured in kilograms. An editor had recently suggested that the tangent was confusing (hidden up in the "clarify changes over the past 100 years" section), and another editor had changed the new mass of a hypothetical 1 Kg mass to 1 Kg - 50 micrograms instead of 1 Kg + 50 micrograms.

In the same paragraph, does anyone know why the official standard and it's copies are only of "roughy the same materials" when the previous paragraph describes them as all being "an alloy of platinum and iridium of 39 mm height and diameter"? In other words, what source did the content of the offical standard come from, so I can check to see that the standard and its copies are of the same alloy? Enuja 02:03, 9 January 2007 (UTC)

Kilogram in Popular Culture

While I doubt the kilogram makes many appearances in pop-references, it did just get mentioned in the latest Dinosaur comic:

http://www.qwantz.com/index.pl?comic=917 --MacAddct1984  03:33, 13 January 2007 (UTC)

The U.S. uses it as a primary measurement?

I want to know where this comes from. all I've been old they've ever used is the Imperial System, not this one. If I remember,they wanted this to be DIFFERENT... I'm likely wrong, though. So, to my understanding, this article seems to be focussing mainly on the U.S. with possible false information. Any Clarification would be good. --SBKT 16:31, 20 March 2007 (UTC)

The pound is defined in terms of the kilogram these days, so the pound's primary reference is the kilogram. I don't think anybody is arguing that the kilogram is in everyday usage (except in NASA).WolfKeeper 16:45, 20 March 2007 (UTC)

It's in common usage in the UK and Europe, and I'd imagine it's used in high-school level science and above in the US- constants like g and M_e use Kilograms as factors, and pV = nRT should use Pa as the unit for pressure right?81.77.175.47 14:53, 8 June 2007 (UTC)

Why is the US mentioned explicitly here? There is no need for it. It is phrased awkwardly, and adds no value.

I'm pretty sure Wolf was referring to everyday usage in the US. It's a well known fact that the kilogram has mostly been accepted for everyday usage in most of the rest of the world Nil Einne 12:26, 19 July 2007 (UTC)

the pound is metric

The current third paragraph is misleading. A pound is exactly 453.59237 grams. No appoximations needed. I will rewrite when I get around to it.CorvetteZ51 17:09, 14 April 2007 (UTC)

The current precision is a compromise, and I think, a good one. There is no need to for 8 significant digits in a lead section. Enuja 19:27, 14 April 2007 (UTC)

Proposed WikiProject

Right now the content related to the various articles relating to measurement seems to be rather indifferently handled. This is not good, because at least 45 or so are of a great deal of importance to Wikipedia, and are even regarded as Vital articles. On that basis, I am proposing a new project at Wikipedia:WikiProject Council/Proposals#Measurement to work with these articles, and the others that relate to the concepts of measurement. Any and all input in the proposed project, including indications of willingness to contribute to its work, would be greatly appreciated. Thank you for your attention. John Carter 21:06, 2 May 2007 (UTC)

Redefining the kilogram

The latest on one of the attempts to redefine the kilogram [3] Nil Einne 07:14, 15 June 2007 (UTC)

http://www.reuters.com/article/scienceNews/idUSSYD9740620070615

Already added as a reference to the article.JimDunning 13:10, 16 June 2007 (UTC)

Bravo & a proposal

Bravo to User:Greg L for doing some needed heavty-duty article improvement in the past days. I do have one suggestion; I know it is generally accepted to start with a History section, but it feels to me as if this article jumps in too hard and too fast to details most people will skip right over. I suggest a different organization. How about we start first with what is now "Link with weight," rename it to something like "Common use" and put the lead section approximate weight and some other example masses (like gram does) in this new section. How does this sound?

On a side note, do the current "examples" in "link with weight" belong in "SI multiples?" Enuja 19:06, 11 August 2007 (UTC)

Thanks for the ‘attaboy’ Enuja. I saw all that disorganized stuff below (“Ugh” factor) and let it lie. I had already spent more time than I bargained for making the computer-generated ray-tracing and editing all that text. Given your prompting, I waded in again. Fixing the rest necessarily entailed the removal of some rather spurious writings, which I am loath to do as it often results in revertings that undoes a lot of hard work. I’ve revised and reorganized everything from the opening definition through “Stability of the International Prototype Kilogram.” I think the article reads better now; it’s certainly makes more accurate and factual statements. Greg L (my talk) 18:01, 12 August 2007 (UTC)

"Mass vs. weight" section

I deleted the section for two reasons. First, the concepts are covered in weight and don't need to be replicated here. Second, because it contains speculative statements (referring to people wanting to know how much "heft" there is) combined with inaccurate statements - such as an unqualified claim that weight=force due to gravity. The narrow definition of weight is only force due to gravity is specific to scientific and engineering contexts, while in general use, weight can either mean force due to gravity or mass. See weight for more on that. --Yath 08:01, 12 August 2007 (UTC)

A different “mass vs. weight” section was already there to begin with so your opposition based on the fact that the topic is also covered in the Weight article is severely undermined. I note too that what had been there previously also made “speculative statements” about what people intend (except that what was written there made no common sense). Further, it seems to me that a good discussion of mass vs. weight solidly belongs in an article on the kilogram. Since I feel one way and you another, the proper Wikipedia way is to have a vote. That's certainly a more equitable way of handling such a radical edit (wholesale deletion) and makes the decision according to the consensus of the Wikipedia community. Accordingly, I've placed the text back in so readers who want to vote can see the text in question in the proper context. I’m particularly interested in what Enuja’s vote will be; she seems to be a frequent contributor to the article.

Greg L (my talk) 08:24, 12 August 2007 (UTC)

So…

This vote was called a bit hastily, don't you think? --Yath 09:11, 12 August 2007 (UTC)

Beats a reverting war. Can you live with it as currently revised or shall we press to a vote? Greg L (my talk) 09:26, 12 August 2007 (UTC)

With all due respect, there is a third option (along with revert war and vote) called "discussion", which I prefer. Note that that's how I began this interaction, with the hope that other editors might follow suit. At any rate, with the threat of reversion looming, I certainly won't go toe-to-toe with you on the undo button.

Getting back to the subject, I don't find arguments along the lines of "this is how we have done it, thus it must be right" to be at all convincing (A different “mass vs. weight” section was already there to begin with). I prefer to concentrate on questions of how the article is served, and whether it is improved or degraded by certain content. So, with respect to the proposition that "shorter is better", we have material regarding the basic differences between mass and weight, which are discussed in at least three other articles (weight, pound (mass), and pound-force). You may understand why I find it counterproductive to bulk up yet another article with the same material. --Yath 22:02, 12 August 2007 (UTC)

Yath, I'll take your recent contribution to the section in question as a sign of an armistice — if not a declaration of peace. I'm OK with what you wrote in your edit. Accordingly, I've deleted the voting-related stuff from the article itself (the editors note). Greg L (my talk) 01:56, 13 August 2007 (UTC)

The length of this section rather interrupts the article's exposition on kilogram - it ought to be either 1. moved to later in article, 2. greatly reduced in size, AND/or 3. briefly discussed with a link to the appropriate article - (which I'd think would be a section in the mass article) --JimWae 03:58, 14 August 2007 (UTC)

I broke it into sub-sections. That goes a long ways towards making it more reader-freindly. Greg L (my talk) 22:49, 15 August 2007 (UTC)

Spelling: National conventions

Wikipedia’s official policy is that the spelling convention used by the first major contributors should be retained. The Kilogram article is written throughout with American spelling (kilogram instead of kilogramme, liter instead of litre). Note the following passage, taken from Wikipedia:Manual of Style:

“ In June 2005, the Arbitration Committee ruled that when either of two styles is acceptable, it is inappropriate for an editor to change an article from one style to another unless there is a substantial reason to do so (for example, it is acceptable to change from American to British spelling if the article concerns a British topic, and vice versa). Edit warring over optional styles is unacceptable. If an article has been stable in a given style, it should not be converted without a style-independent reason. Where in doubt, defer to the style used by the first major contributor. See Wikipedia:Requests for arbitration/Jguk. ”

Note that “liter” is the proper American spelling. Note further that two other instances of liter are elsewhere on the page. Please also take note of another common-sense policy from Wikipedia:Manual of Style:

“ An overriding principle is that style and formatting should be applied consistently throughout an article, unless there is a good reason to do otherwise, except in direct quotations, where the original text is generally preserved. ”

Accordingly, your insistence at “correcting” this one instance just makes the article non-harmonious. It would be highly inappropriate of you — and against Wikipedia policy — to go through the entire article to change the rest of the article to British spelling.

As regards consistency from article to article within Wikipedia, there is none. Note the Pressure article. It uses British spelling throughout. Further, if you click on a link in the article spelled centimetre (of water), you go to an article titled Centimetre of water wherein the spelling within the article uses the “centimeter” spelling!

Wikipedia’s policy (that the spelling convention used by the first major contributors should be retained) seems a good one. It encourages contributors to begin or substantially expand articles. Further, it reduces frustrations for contributors such as when someone later wades into an article (like the Kelvin article, which uses American spelling throughout) and changes “color” to “colour.”

Please adbide by these policies.

P.S. On a final note, I’m not entirely ‘hung up’ on American conventions. For instance I used the European date convention of “7 April 1795” in the History section. It is such a steaming logical way of doing it and eliminates a comma. And although I am an American engineer, I do all my primary design in SI units and only convert to inches etc. at the last step when generating prints for machine shops or writing an owners manual. (19:09, 13 August 2007)

Greg L (my talk) 18:41, 13 August 2007 (UTC)

• I don't keep track of which spelling was originally used on each article - I linked the article to litre in such a way that did not require piping. It is true also that I find the meter/metre variant for meaning useful. You will also find the vast majority of spellings for SI units on wikipedia use -re. I was not "insisting on correcting" - and, being in Canada, I would never myself use the "kilogramme" spelling. The fact that it was not "kilogramme" does not in itself establish that it should be "liter". It seems even in UK "gramme" is often considered archaic. "Litre" was also the exclusive spelling in this article long before your arrival (over 3 years since [4]). Although it was you who made an issue of spelling, so far the first-use policy would support (but not require) your reversion to the non-functional -er spelling that requires piping. But go ahead, make yourself happy --JimWae 18:58, 13 August 2007 (UTC)

• Thank you. I appreciate your flexibility. Our recent edit/edit/edit, while rarely enjoyable, resulted in an improved opening definition. Greg L (my talk) 19:09, 13 August 2007 (UTC)

having originally been defined relative to this volume of water.

a quantity "having originally been defined relative to this volume of water" could have been "relatively" defined as half that volume. More information is conveyed by the statement (similar to one long included in this article) - that it is "almost exactly equal to" the mass/weight of 1 L of water.

JimWae: You're right. Done. Greg L (my talk) 20:45, 13 August 2007 (UTC)

Proposed organization

Wow, I go away on a measly 3 day vacation to (the excellent) Zion National Park, and this article improves by leaps and bouds! How exciting. Honestly, I've only had it watched to keep it from getting any worse; although this article certainly needed serious work a week ago, I wasn't planning on doing any of it. Bravo again to Greg L for doing so much work on this!

Philosophically, I think that this article should do a quick sketch of the mass v. weight issues, and direct readers over to weight. However, the current mass v. weight section has some details and approaches that are better than the treatment at weight. Personally, I think that User:Greg L should put that section in his user space, we should re-organize this article, and Greg L should edit his stuff into weight to make it excellent as well.

Here is a proposal for the organizational scheme:

 ==Common Use==
 ===Mass versus weight=== link to main article (weight, yes?) contents of current "the distinction between the two" subsection
 ===Converting mass to weight === contents of "unit of measure for weight" and current subsections, shortened and put together
 ==History== (complete with current subsections)
 ==Stablity of the International Prototype Kilogram==
 ==Proposed future definitions== (complete with current subsections)
 ==SI multiples ==
 ==See also==
 ==References==
 ==External links== 

This would remove the current section "The nature of mass" and the contents of the subsections "Effect of bouyancy" and "Types of scales and what they measure," and I'd also like to work on streamlining much of the new content to be a short and readable as possible. How does this organization sound to everyone?

I'm also going to play around with the lead section; everyone, feel free to revert me or fiddle with it. I tried to do a long talk page post last night with lots of detailed wording proposals, but the computer I was using restarted in the middle of the process, so I'm just going to try doing before talking. I'm very willing to talk after doing. Enuja 23:45, 15 August 2007 (UTC)

Wholesale deletion of sections of the Kilogram article

• Well, Enuja, I think you missed your calling; you should’ve been a diplomat. All I can say is that as an engineer, I once pondered all the details about the kilogram that are now covered in the Mass vs. weight section. Of course, that was when I was a younger engineer (before the Internet) and one had to go to scientific papers (subscription… which I didn't do) or other means. One time in the early 90s, I even called the NIST to find out about buoyancy’s effect and how it was compensated for with our kilogram prototypes.

  What I'm inferring from what you wrote above is that my recently-added subject matter is too arcane for inclusion in a Wikipedia article on the kilogram. Having worked for decades with other engineers, I believed I knew how their minds worked (don’t ask) and what they would find interesting. To that extent, I thought I could write from that point of view, which would reliably serve as a microcosm for the engineering-type audience. Perhaps though, it's just me. Or perhaps you don't believe engineers as a group, are really representative of the average Wikipedia reader who will come to this article. Given though, that some Wikipedia articles are brimming with arcane formulas suitable only for mathematicians, I think that what is now there is very middle-of-the-road for an article on a technical subject.

  I note that we four (you, me, JimWae, and Yath), who are currently quite active on this article, all have our opinions on the matter and the votes seem 3:1 against me. Of course, I'm a newcomer and have really stirred the pot this time! I would hope that before large swaths of this information are deleted, you all see how well-received the information is by a wider audience. I would suggest that passages that don’t really belong, soon get deleted anyway in “drive-by shootings” by the average reader after they have a WTF?!?–reaction. Greg L (my talk) 02:41, 16 August 2007 (UTC)

• I think that one of the largest flaws of wikipedia is that the articles keep getting longer and more archane, and I'm a bit of an activist for short & sweet articles. In my admittedly short experience, new editors rarely delete sections (as anything another than vandalism) and people rarely edit things to make them shorter. I DO think that the level of engineering detail in the current version of this article is relevant to the lay leader, and I admit that I'm learning a lot from what you are writing {and isn’t that what any good encyclopedia ought to do – greg}. However, the effect of buoyancy and the difference between a scale and a balance applies to more than just kilograms; it applies to the general measurement of mass (and weight). Therefore, I think that much of your very useful engineering detail should go into weight and mass with links from this article to those sections. I have not even read weight and mass, however, so I don't yet know exactly where all of your information should go, and how much should stay in the article. I do think things like the inclusion of and link to kilogram-force are really vital parts of the article. I need to buckle down and do some actual work, though, so I am very much willing to let the article sit as-is for the moment. Enuja 18:59, 16 August 2007 (UTC)

I must repeat that the section on mass & weight, as good as it is, is NOT specific to this article & interrupts the exposition of the main topic. It needs a new home - either mass or weight or an article of its own --JimWae 01:30, 19 August 2007 (UTC)

Look, eventually this section will get removed - because it just does not really belong here. It would be a shame if it just disappears rather than finds a good home --JimWae 04:30, 19 August 2007 (UTC)

• I went and did it. So much for me being diplomatic.  :-( I wanted to wait and let you do it yourself, Greg L, but you continued to work on trying to making your good engineering explinations fit into this article. The stuff you wrote needs to go, variously, into mass, weight and weighing scale, or a new article called something like mass versus weight. I think it would be much more useful for you to spend time making your recent contributions fit into those articles instead of making them fit into this article. If you don't do it, I will; I'm not going to let your good explinations of bouyancy and a bunch of other things just go away.

I think I've left the correct amount of information, but it needs to be tied together a bit more (and I like the moon rather than the tire example-- why did you change that, Greg L?) and I would greatly appreciate if someone else came up with a better name for the section. Enuja 05:06, 19 August 2007 (UTC)

Taking perfectly good encyclopedic information that is geared very specifically to the topic of the kilogram and deleting it in the name of keeping articles "short & sweet" really compromises the quality of the encyclopedia; you end up with a squeezy Collier's Encyclopedia suitable for children rather than a tool suitable for serious work. Taking JimWae's comment to heart that the section “interrupts the exposition of the main topic,” I moved the section down near the bottom of the article. Jeez, I created the graphic, completely rewrote the history section (which was incorrect junk before), and some of you are objecting to one section—not because any of it is “wrong”—but because one can find some (but by no means all) of the information by digging around elsewhere on Wikipedia. Come on At 27 kB, this article isn’t at all big by Wikipedia standards and wholesale deletion of relevant information is uncalled for. Greg L (my talk) 07:33, 19 August 2007 (UTC)

Greg L, you misunderstand my intentions. I want users of this encyclopedia to be able to find out how the bouyancy of an object effects how it is massed. I want users to understand the difference between mass and weight. And I want users to be able to FIND these things. Putting the best treatment of these subjects into kilogram is HIDING the information away from people who want to find it. You can be more than an editior of kilogram; you can make the treatment of bouyancy in massing and wieghing (which might even deserve its own article!) really really understandable and easy to find. It isn't going to be easy to find if it's tossed away into an article about one specific unit of mass. Yes, your good explination should be linked from kilogram; it should also be linked from pound (mass) and a TON of other places. Wouldn't it be silly to link from pound (mass) to here to explain the effect of bouyancy on massing? The first thing I posted on this talk page after you started your really impressive improvement of this article was a Bravo, and I wasn't kidding. I also posted a suggestion about re-organization to prevent you from doing work that would just be reverted.

I'm really impressed and grateful for your work on this article. Instead of being upset at some of us for giving you trouble about "one section," realize that the reason I am giving you trouble is that I don't want you to waste your effort making something fit in a place that it isn't going to stay. Even before you put it back at the bottom of the article, the stuff you wrote was still there in the history, and I am planning on finding a good place for it, that it can be linked to from lots of relevant places, so MORE PEOPLE will be able to read it and gain understanding. I am not worried that this article is too long; I am worried that this article is not what a reader is looking for when they type in "kilogram." Enuja 19:38, 19 August 2007 (UTC)

• Very well. I appreciate your thoughtful answer. However, there is a practical limitation inherent in Wikipedia that makes doing what you propose untenable. Also, there is an editorial reason for keeping a copy of the information here. I'll touch upon the latter first (the editorial reason): Closely-related information should be available in a single article; that’s why encyclopedias like Brittanica have some depth to their articles. Not that I’m advocating going into that much detail, but 27 kB is far from being Brittanica-like and this article is still quite succinct. So let’s look at how closely-related the information is. The “Mass vs. weight” section deals with five sections:

1. The distinction between the two
2. The unit of weight: kilogram-force
3. Converting mass to force
4. Buoyancy and “conventional mass”
5. Types of scales and what they measure

The first one (“The distinction between the two”) is short. Also, common-sense clearly shows it belongs in an article on the kilogram. Notwithstanding that someone might be interested in the concept of ‘mass vs. weight‘ in its own right (there is, after all an article on just this topic), it makes too much sense that someone reading an article on the kilogram would be interested in a single, succinct paragraph about how the kilogram isn’t technically a unit of weight. This clearly is quite topical to the subject of the kilogram given that common usage of the word ‘kilogram’ is often in the context of “weight.”

The second one, “The unit of weight: kilogram-force”, clearly is highly relevant and topical to the subject of the kilogram. It directly addresses the distinction between the common usage of a “kilogram of weight,” and what the unit of measure really is. This article is clearly a highly suitable place for the information.

The third, “Converting mass to force”, is geared specifically to the converting from the kilogram to newtons. It is not a generalized text on the broad concept. Accordingly, it too solidly belongs here in the Kilogram article (and possibly too in the Newton article).

The fourth, “Buoyancy and ‘conventional mass’ ”, deals specifically with mass standards. What would you propose(?) create a new Wikipedia article on mass standards? Even if one did create such a page, this information is obviously still highly relevant and belongs here.

The fifth, “Types of scales and what they measure” is a short paragraph that ‘connects the dots’ about the real distinction of what technically determines the difference between a kilogram and a kilogram-force.

Lastly, the first limitation I cited: the “practical limitation.” Spreading this information all about Wikipedia just exposes it to decay and degradation as it gets edited and and deleted in (now-multiplied) “drive-by shootings.” That’s the downside of Wikipedia.

Your quest to keep articles “short and sweet” is at odds with the very nature of what Wikipedia is about. Wikipedia articles are supposed to grow and expand, otherwise, it would still look as it did in its very beginnings. As long as added information is topical and relevant, the articles improve. Again, at 27 kB for a technical article, this one is still far from bloated. There is no valid reason for anyone to wade through any Wikipedia article and do wholesale deletions on entire sections just because they feel the text could arguably also fit elsewhere. Perhaps the section in question would fit well in other articles too (and should also be copied to these other articles). However, they are clearly topical and relevant to the kilogram, the article isn’t ‘big’ by any means, and wholesale, industrial-strength deletions of entire passages—unless they clearly have little to do with the article—isn’t the Wikipedia way.

If everyone else tried to do what you’re doing, Wikipedia wouldn’t have grown into what it is. It would be a supremely frustrating place to contribute to if others deleted recently added information in the name of keeping already-short articles “short(er) and sweet(er).” Enuja, I think Wikipedia articles would benefit if you expanded them with additional, encyclopedic information, rather than delete other’s work. You’ve got to stop doing this unless the information just plainly doesn’t belong. Greg L (my talk) 22:59, 19 August 2007 (UTC)

Greg L, when you call my recent edits "wholesale deletion" you neglect that 1) I plan on putting your very good information back in different articles if you don't do it before I do (I'm waiting because I'd rather that words written by you come from your account when people look back at the histories of the articles) and 2) I did keep short paragraphs on the difference between mass & weight, the kilogram-force, and types of scales and what they measure. I'm not trying to toss information away or hide it in lots of hard to find articles, I'm trying to help organize the encyclopedia so that people can find what they want. I'm trying to make maintenance and linking easier, not harder. I want to work with you; I don't have the information you have, and what you are contributing to this encyclopedia is very useful. I can help by editing the article to be in simpler grammar with smaller words that mean the same thing, and by helping to re-organize the articles. Please, let's work collaboratively so that the end result is not just a better article, but a better encyclopedia. Enuja 00:36, 20 August 2007 (UTC)

Enuja: Your efforts, while well-intentioned, are not going to be well-embraced if your first act in this process is to simply delete the hard work of other contributors. That methodology is seriously flawed. Greg L (my talk) 01:37, 20 August 2007 (UTC)

(unindent) My first act was to say Bravo! on this page and suggest a different organization. My second act was to propose an organization in more detail while highlighting my agreement with other editors that the mass v. weight section was out of place in this article. Then I waited, as you asked me to, to see what other people thought and what reactions the section would get. However, you did not wait. You kept making the section longer, when the other three editors on this page had all said that it should be shorter and should link to other sections. For my third act, about three days after my second proposal, I edited the section, keeping a lot of the information you had added, and removing the things I had suggested above should be removed. To me, this is the very opposite of simply deleting as my first act. Enuja 02:54, 20 August 2007 (UTC)

• OK, swell. Pat me on the head with “Bravo”, wait three days, and then delete the stuff. Someone once said “Diplomacy is the art of telling someone to ‘go to Hell’ and making them think if was their idea to do so.” Only after I go there (blazes), I stop and realize “Hey, Enuja just deleted all my stuff (but she gave me a ‘smiley face’ on the way).” ;-) Greg L (my talk) 04:31, 20 August 2007 (UTC)

Request for Comment: Scope of Kilogram article

Template:RFCsci How much information about "Mass versus weight" and the methodology of measuring mass should appear in Kilogram? 00:22, 20 August 2007 (UTC)

Statements by editors previously involved in dispute

• The article kilogram should cover information specific to this particular unit of mass, and the very useful information added by User:Greg L about the effect of bouyancy on measuring mass and the difference between mass versus weight should appear in articles such as mass, weight and weighing scale so that this information is available to all interested users, and not hidden away in the kilogram article. Having duplicate content in multiple articles makes keeping the content correct and up to date much more difficult. As this information is precisely as relevant to articles such as pound (mass) as it is to kilogram, the information should be in articles that are linked to from both kilogram and pound (mass) as well as from a variety of other articles. Enuja 00:22, 20 August 2007 (UTC)

• The section in question — Mass vs. weight — is encyclopedic, topical, and quite specific to the kilogram. The issue should be considered and resolved on this basis only:

  Is the information…

1. informative to the typical visitor to this article,
2. interesting to the typical visitor to this article, and
3. does it enhance the article.

If others feel the information—when placed in the Kilogram article—is “hidden away,” they are always free to place variations of relevant passages elsewhere in suitable articles throughout Wikipedia. Greg L (my talk) 01:31, 20 August 2007 (UTC)

I have to disagree that it is specific to the kilogram. It could apply equally to any unit of mass, such as gram or pound (mass). It makes sense to mention the subject in each of these articles, but it does not make sense to cover it completely. There is only one place for that: weight. The alternative would be to duplicate the information in all articles related to units of mass - which is clearly not appropriate. --Yath 23:09, 20 August 2007 (UTC)

Comments from others

1) KEEP. Why was this even brought up for a vote? The section is extremely informative and touched on stuff I wouldn't have known to go looking for. Signed: Rob Fry (I'm not a regular Wikipedia author and I don't know how to sign my name) —The preceding unsigned comment was added by 66.108.28.133 (talk) 02:03, August 20, 2007 (UTC)

To sign your posts on talk pages, simply type four tildes (~~~~). Also, wikipedia operates on the basis of consensus, not votes. Enuja 02:17, 20 August 2007 (UTC)

2) FIND A BETTER HOME - this section, as good as it might be or become, is only marginally about the kilogram - and not at all specific to the kilogram. AND, it is not nearly as good as it could be. While it might be technically accurate (nearly without error), it is not succint, and does not stick to one topic at a time. Nor is it anywhere near comprehensive - it mentions that air pressure can slightly affect weight, but never mentions that weight can change drastically or even be (nearly) zero (a fundamental difference). It needs to be improved, moved, & -- after a very brief summary -- linked to from this article & numerous others--JimWae 07:32, 20 August 2007 (UTC)

• Jim, quoting you: “…but never mentions that weight can change drastically or even be (nearly) zero…” Yes it does. In the first footnote in the section in question. There, it says “Masses with densities less than that of air float and have negative weight; that is, they are buoyant. Such masses have weight in a vacuum.” This article would swell to the size opposed by Enuja if every single scientific exception was elobrated upon in-depth right in the main body text. Details such as this are best delt with via footnotes. Also, let's get a good consensus from a wider constintuency of Wikipedia than just Jim, Greg, Enuja, and Yath. We all know each of us has strongly-felt opinons. We should obtain the opinions from people who are less biased. Greg L (my talk) 17:33, 20 August 2007 (UTC)

• are you suggesting I not have an opportunity to present my opinion here, but you do? There IS STILL NO MENTION of drastic change in weight on moon & in space - fundamental aspects more easily understood than buoyancy. Btw, helium balloons have weight everywhere on earth - they just weigh less than the air they replace - they have "negative" weight relative to air - but not any kind of absolute negative weight. With respect to weight, all this article needs to discuss is how kilograms are often presented as units of weight (as in: How many kg do you weigh?) - even on medical documents - and that such usage is inexact, but not any big deal since we don't really think that by going to the moon, one's body content is drastically reduced. Buoyancy is a detail, near-zero weight outside a gravitational field is fundamental --JimWae 20:04, 20 August 2007 (UTC)
• Based on your text, one would easily get the idea that the hallmark difference between mass & weight is buoyancy - and that the weight of a helium balloon actually increases (from negative to zero) as its distance from Earth increases --JimWae 20:43, 20 August 2007 (UTC)

• Point taken JimWae. Of course your opinion matters and I added some proposed text to accommodate your suggestion. As with all Wikipedia articles, you are free to sincerely edit what I just added. And given that you are the origin of this “moon-gravitiy” topic, I would be pleased to afford you great latitude with your edits on this issue. There are two issues simultaneously at play here: 1) the very existence of these sub-sections in the Kilogram article, and 2) sincerely editing what I've added to make it better. The opening definition has benefited immeasurably by sincere, multiple back & forth edits by all of us. The product is now a pithy, tight, well-crafted paragraph. Wikipedia has benefited from this. Greg L (my talk) 22:00, 20 August 2007 (UTC)